Fibrosis in horses refers to the formation of excess fibrous connective tissue as a reparative or reactive process following injury or inflammation. This condition can affect various organs and tissues, including the lungs, liver, and skin, leading to impaired function and structural changes. Fibrosis is characterized by the excessive deposition of extracellular matrix components, such as collagen, which can result in tissue stiffness and scarring. In equine medicine, fibrosis can be associated with chronic conditions such as equine asthma or hepatic disease. This page compiles peer-reviewed research studies and scholarly articles that investigate the mechanisms, diagnosis, and management of fibrosis in horses, offering insights into its impact on equine health and potential therapeutic approaches.
Nixon AJ, Stashak TS, Smith FW, Norrdin RW.Carbon fibre-polylactic acid composites and monofilament non-absorbable suture material were compared for the repair of surgically transected superficial digital flexor tendons in 10 horses. All surgical wounds healed by first intention. The repaired tendons were enlarged, the carbon implanted tendons being larger than those sutured. The horses were killed at six, eight, 12,20 or 24 weeks. Greater fibrous thickening occurred in tendons repaired with carbon fibre, especially at 12 weeks postoperatively. Carbon fibre incited a greater histological response with macrophages, lymphocytes, plasma c...
Mullaney TP, Brown CM, Watson GL, Brandt LA.An apparently new and emerging fatal hepatic disease affecting foals is described. Characteristics included evidence of hepatic failure, marked biliary hyperplasia, hepatocellular necrosis and occasionally fibrosis. Generally, the features of the disease appear to differ markedly from other hepatic diseases of neonatal foals.
Turner AS, Trotter GW.The case histories of 18 horses with hindlimb lameness attributed to fibrotic myopathy were reviewed. In 14 horses, the problem developed after trauma. In 5 others, it developed secondary to intramuscular injections. Other causes of the lameness were surgery, exertional injuries, and purpura hemorrhagica. Eleven of the horses were treated by resection of scar tissue or by semitendinosus myotenotomy. Postoperative complications included pressure necrosis under quill sutures (9 horses), acute disruption of the skin incision (2 horses), dehiscence of the wound during healing (2 horses), and prolo...
Williams IF, McCullagh KG, Silver IA.During tissue response to injury the glycoproteins fibronectin and Type III collagen are synthesized in increased amounts. We have studied the distribution of these molecules in the healing tendon at various times after injury by comparison with that of the major constituent of normal tendon, Type I collagen. Immunofluorescent localization demonstrated the presence of fibronectin throughout the tendon within one week after injury. Staining was found in the matrix, both around capillaries and around fibroblast-like cells. Fibronectin was still apparent in the healing tendon at one month after i...
Divers TJ, Warner A, Vaala WE, Whitlock RH, Acland HA, Mansmann RA, Palmer JE.Eight foals, 2 to 5 days of age, with similar clinical signs and laboratory and pathologic findings, died from hepatic failure. The predominant clinical signs were depression and icterus. Abnormally high values were found for plasma ammonia content, aromatic-to-branch-chain amino acid ratio, total serum bilirubin content, gamma glutamyl transferase activity, alkaline phosphatase activity, and PCV; partial thromboplastin time and prothrombin time were prolonged. Some foals had high sorbitol dehydrogenase activity. These laboratory findings were suggestive of subacute hepatic disease and failure...
Barber SM, Clark EG, Fretz PB.In 2 horses with rapidly growing, locally destructive tumors of the premaxilla, there was major disruption and displacement of some incisor teeth, with radiographic evidence of disruption of the premaxilla at the base of the tumors. In horse 1, most of the tumor was removed by incising it at its base, and the tumor bed was treated cryosurgically with 3 freeze-thaw cycles, using liquid nitrogen. The area healed by 2nd intention. The tumor was found to be a benign fibroblastic tumor, possibly a fibroma. After 4 years, there has been no recurrence. Horse 2 was euthanatized on the basis of a tenta...
Eagle MT, Koch DB, Whalen JP, Hintz HF, Krook L.The left thoracic limb was immobilized in a plaster cast in 6 grade weanling ponies for 6 weeks. Two ponies were injected intramuscularly each day with 2.4 micrograms of 25-hydroxycholecalciferol [25(OH)D3] per kg bodyweight, two with 1.2 micrograms and two received no injections. Immobilization of 25(OH)D3 treatment had no significant effect on mineral metabolism. Immobilization resulted in significantly decreased weight and specific gravity of metacarpus III (MCIII). Histologic examination and triple fluorochrome incorporation showed that the osteopenia was caused by atrophy of osteoblasts w...
Williams IF, Heaton A, McCullagh KG.The connective tissue composition and organisation of the "equine sarcoid" was compared with that of normal adult equine skin to determine whether the cells which produce their respective connective tissue matrices show similar biosynthetic characteristics. No major qualitative difference could be found between the collagen compositions of skin and sarcoid material, although the organisation into fibres of Type III collagen in the sarcoid was markedly greater than that of skin.
Miller RI, Campbell RS.A survey of granulomatous and neoplastic diseases of the skin of horses of tropical north Queensland was carried out during the period 1970-1980. Of 338 horses affected, 46.4% suffered from equine fibrosarcoma (sarcoid), 30.2% from phycomycosis, 7.4% from squamous cell carcinoma, 6.8% from other tumours, 4.7% from cutaneous habronemiasis and 4.4% from exuberant granulation tissue. Most specimens were submitted during the first half of the year after the wet monsoonal season and significantly more diseases originated during the first quarter. There was minor variations with breed, age and sex s...
Adams SB, Fessler JF, Thacker HL.FIBROMAS arise from connective tissue and occur in all domestic animals (Smith, Jones and Hunt 1972; Stannard and Pulley 1978). They are most frequently noted in the dermis or subcutis, but may be present wherever connective tissue occurs. In the dermis and subcutis of the horse fibromas are grossly similar to sarcoids and may be difficult to differentiate (Baker and Leyland 1975). Fibromas have been described as tumours of the tendon sheath or tendon proper in man (Flynn 1975), but have not been described in this location in the horse.
Leishman D, Miller RB, Doig PA.The density of uterine glands, height of surface epithelium, numbers of hemosiderin laden macrophages, inflammatory cells and layers of periglandular fibrosis were evaluated in uterine biopsies from 40 mares. These features were found to be highly variable in normal equine endometrium. Minor pathological changes appeared to be masked by this normal variability. Atrophy of uterine glands was recognized in mares which had been barren for more than three years. No significant differences were found between barren and normal mares in the height of epithelium, number of hemosiderin laden macrophage...
Barber SM.A three year old Thoroughbred filly was examined because of bilateral nasal discharge and external swelling of the left laryngeal area. Endoscopy revealed an enlarged left arytenoid cartilage, left laryngeal hemiplegia and drainage of purulent material into the lumen of the larynx. Radiographs showed a large fluid and gas filled cavity overlying the caudal larynx and cranial trachea. Surgical drainage and debridement of the abscess led to complete healing by secondary intention. Laryngeal ventriculectomy was performed as a treatment for left laryngeal hemiplegia, but a grave prognosis for resp...
Muylle E, Vandenhende C, Oyaert W, Thoonen H, Vlaeminck K.Thirty-two horses were examined with a history of poor performance and unthriftiness several months after the ingestion of feed containing monensin sodium. Cardiac abnormality was diagnosed in 8 cases and suspected in 4 others. Necropsy examinations were performed on 6 cases with marked clinical symptoms and evidence of circulatory failure was found. Marked cardiac myopathy and fibrosis was a consistent feature. It is concluded that ingestion of monensin sodium by horses may cause either acute death or delayed cardiac circulatory failure as a result of specific cardiac myodegeneration.
Irwin DH, Howell DW.An easy diagnostic technique for recognising fibrotic myopathy and scarring in the caudal popliteal area is described. A simplified corrective surgical technique is offered and discussed briefly. Some aspects of haematomas are reviewed.
Doig PA, McKnight JD, Miller RB.The results of a study on endometrial biopsies obtained from 700 infertile mares are reported. Infiltrative endometritis was present in 51% consisting of a combination of an acute and chronic cellular response in 6%, mild chronic infiltrations in 35% and moderate to severe chronic infiltrations in 10%. Demonstrable endometrial fibrosis was found in 88% of the mares with the majority having mild (51%) or moderate (35%) changes. The age of the mares and the average number of years barren gradually increased with the severity of endometrial fibrosis, as did the combined incidence of fetal loss (e...
Angsubhakorn S, Poomvises P, Romruen K, Newberne PM.Two episodes of acute aflatoxin poisoning in horses suggest that horses are susceptible to the toxic effects of this mycotoxin. Lesions associated with exposure to aflatoxin included encephalomalacia of cerebral hemispheres, fatty degeneration, necrosis, bile duct hyperplasia, fibrosis of the liver, fatty infiltration of the kidney, hemorrhagic enteritis, and myocardial degeneration. Hypoglycemia, hyperlipidemia, and depletion of lymphocytes accompanied these lesions. The diagnosis was based on gross and histopathologic observations, consistent with observations of other species poisoned with ...
Cranley JJ, McCullagh KG.The hearts and aortas of 2076 unselected horses of all ages were examined immediately after slaughter. Focal zones of fibrosis, observed in the myocardium of 14.3 per cent of hearts examined, were found in both atria and ventricles and were unrelated to age. Microscopically the majority of lesions involved myocardial fibre lysis and replacement fibrosis, although acute infarction was present in some cases. Intramyocardial arterioles in or adjacent to the lesions exhibited occlusive arteriosclerotic changes whereas those elsewhere remained patent. The evidence strongly suggests that the myocard...
Button C, Scrutchfield WL, Clark RG, Knauer KW, Schmitz DG.A variety of atrial dysrhythmias including paroxysmal atrial tachycardia, atrial tachycardia with 2nd-grade atrioventricular block, atrial fibrillation, and atrial flutter developed in a 5-year-old Quarter Horse gelding. Quinidine and propranolol were not successful in restoring normal sinus rhythm. Sinus rhythm was re-established during digoxin therapy, but later reverted to atrial dysrhythmia. At necropsy, multiple, discrete pale areas were found on both atria and the interatrial myocardium. Histologic examination of these lesions demonstrated myocytolysis and replacement by fibrous connecti...
Williams IF, Heaton A, McCullagh KG.The histological appearance of cells and tissues in the reparative scar tissue which forms in the equine superficial flexor tendon following partial rupture was compared to that of normal tendon. The repair fibroblasts were found to be larger and more basophilic than the tenocytes of normal tendon, to have large vesicular nuclei and to resemble the 'myofibroblasts' described in scar tissue elsewhere. The cell to matrix ratio in scarred zones of tendon was found to be increased and the concentration of collagen in these areas was less than in normal tendon. However, the scar tissue collagen was...
Elinder CG, Jonsson L, Sternström T, Piscator M, Linnman L.The hardness of drinking water (i.e., the sum of calcium and magnesium concentrations) has been related to cadmium concentration in kidney cortex and to microscopic signs of arteriosclerosis and focal myocardial fibrosis in 50 Swedish horses slaughtered for meat production. A significant negative correlation was found between water hardness and cadmium concentrations in kidney cortex. This indicates that horses living in soft water areas are more inclined to accumulate cadmium from the general environment. Microscopic changes in the aorta and myocardium were approximately 2 times as frequent i...
Jackson DS.This paper reviews some of the biochemical modifications involved in fibrous tissue formation and discusses possible ways of controlling fibrosis in clinical conditions. The lathyritic agents, beta-aminoproprionitrile (BAPN) and penicillamine, appear in certain situations to be able to control fibrosis by blocking the biosynthesis of collagen. There are no compounds that are yet known which are capable of reversing pre-existing fibrosis and future research may perhaps be more profitably directed towards the stimulation of collagen catabolism rather than the inhibition of its synthesis.
Mather EC, Refsal KR, Gustafsson BK, Seguin BE, Whitmore HL.Intrauterine fibroscopy was used in the clinical evaluation of 40 mares with established histories of subfertility. The average age of the mares was 12.2 years with a 2.8-year interval from last foaling in multiparous mares. Transluminal adhesions, endometrial cysts, diffuse fibrosis, fluid accumulation or myometrial tumours were found in 26 mares. When compared to other techniques, fibroscopy did not seem to be superior to uterine biopsy but had some advantage over rectal palpation as a single diagnostic technique. Only 3 mares failed to exhibit pathological findings when all 3 techniques wer...
O'Sullivan BM.The clinical signs and pathology of 6 field cases of a respiratory disease of horses which occurs in the coastal hinterland of south-eastern Queensland are described. The condition has occurred for many years and has been thought to have been associated with ingestion of Crofton weed (Eupatorium adenophorum). Coughing, rapid heaving respiration, decreased exercise tolerance and loss of condition were seen in affected horses. In longstanding cases fibrosis, alveolar lining cell proliferation, oedema, neutrophil infiltration and abscessation were seen. In some cases vascular thrombosis and infar...
Barthold SW, Olson C.Cultured cells from bovine papilloma virus (BPV)-induced fibroblastic tumors and normal dermis of cattle, horses, and hamsters were examined for cell membrane or internal neoantigens, using the indirect immunofluorescence technique. Sera from cattle and horses bearing BPV-induced fibromas cross reacted with cell membranes of tumor, but not with normal dermal cells of both species. The reaction could be blocked with homologous, but not heterologous, serum of these 2 species. Immunofluorescence was not detected with sera from hamsters bearing BPV-induced sarcomas if incubated with bovine, equine...
Kenney RM.Normal histologic changes that occurred in concert with the ovarian cycle were evaluated. When combined with behavioral and physical findings, this evaluation enabled determination when there was synchrony between ovarian steroids (estrogen and progesterone) and their target tissues of endometrium. A system for classification as well as definitions of patterns types and degrees of severity of inflammatory and fibrotic changes was developed to facilitate a uniform system for description and communication. An attempt was made to relate the pathologic changes to their effect on fertility when fer...
Walthall JC, McKenzie RA.Horses grazing manily Cenchrus ciliaris and/or Panicum maximum var. trichoglume pastures on over 30 properties in southern central Queensland developed lesions of osteodystrophia fibrosa. Horses on individual properties in coastal Queensland grazing Setaria anceps, Brachiaria mutica or Pennisetum clandestinum also developed the disease. Ill-thrift, lameness, and fibrous swellings of nasal bones, maxillae and mandibles were observed. Calcium and phosphorus levels of pasture were normal but all the above pasture species contained oxalates which were suspected of causing the disease.
Miragliotta V, Lefebvre-Lavoie J, Lussier JG, Theoret CL.Horses suffer from a debilitating impediment in repairing wounds located on the lower limb that leads to the development of a fibroproliferative disorder (exuberant granulation tissue). This condition is a source of wastage since it often forces retirement from competition. Treatments that resolve or prevent this condition are still lacking, maybe due to deficient knowledge of the underlying molecular mechanisms. Fibroblast-to-myofibroblast conversion is an essential step allowing contraction during wound repair and is accompanied by an increase in OB-cadherin expression. Objective: To clone e...
Suarez-Fuentes DG, Tatarniuk DM, Caston SS, Kersh KD, Gillen AM, Hays AM.To compare outcomes after semitendinosus tenotomy performed under standing sedation versus general anesthesia. Methods: Retrospective case series. Methods: 20 horses with fibrotic myopathy of the semitendinosus muscle. Methods: Medical records (2002-2015) of horses undergoing tenotomy of the semitendinosus muscle for the treatment of fibrotic myopathy were reviewed. Signalment, history, affected muscles, restrain method, surgical procedures, and short-term outcome as well as complications were retrieved from records. Long-term outcome (gait and athletic function) was assessed at least 6 months...
Harvey KA, Morris DD, Saik JE, Donawick WJ.A 13-year-old Thoroughbred mare had a 2-week history of weight loss and intermittent fever. Examination of abdominal and pleural fluid revealed peritonitis and pleuritis. Ultrasonography of the ventral abdominal midline revealed an intra-abdominal mass. Exploratory celiotomy was performed, but the mass was not surgically excisable. The mare was euthanatized and necropsied. Histologically, the mass was determined to be a fibrosarcoma of omental origin.
Roels S, Ducatelle R, van De Vijver B, De Kruif A.An 18-month-old cross-bred Fjord pony colt presenting a fibrosarcoma of the prepuce with severe infiltrative growth, was treated by topical application of 5-fluorouracil. Biopsies were taken before and after a treatment period of 2 months. As a control, preputial tissue from a healthy horse was biopsied. Tissue sections were stained immunohistochemically for Proliferating Cell Nuclear Antigen (PCNA) and Proliferation related factor--Ki67 (MIB1). Using computerized quantitative image analysis of these sections, Mitotic index (PCNA), Growth Fraction (Ki67) and total nuclear area percentage of th...
Barton AK, Gehlen H.The term remodeling describes the process resulting in a tissue that is structurally and architecturally altered compared to its healthy counterpart. At least in severe equine asthma, this occurs mainly, but not exclusively, as a consequence of neutrophilic airway inflammation and is characterized by hypertrophy of the smooth muscle layers in airway and arterial walls as well as fibrosis of the bronchial walls and pulmonary interstitial tissue. To date, much less is known for mild to moderate equine asthma. For a long time it was assumed that these processes are irreversible, and at least for ...
Divers TJ, Warner A, Vaala WE, Whitlock RH, Acland HA, Mansmann RA, Palmer JE.Eight foals, 2 to 5 days of age, with similar clinical signs and laboratory and pathologic findings, died from hepatic failure. The predominant clinical signs were depression and icterus. Abnormally high values were found for plasma ammonia content, aromatic-to-branch-chain amino acid ratio, total serum bilirubin content, gamma glutamyl transferase activity, alkaline phosphatase activity, and PCV; partial thromboplastin time and prothrombin time were prolonged. Some foals had high sorbitol dehydrogenase activity. These laboratory findings were suggestive of subacute hepatic disease and failure...
Whitehair KJ, Parker JE, Smith GN, Adams SB, Bottoms GB.Serum levels of type III procollagen peptide (P-III-P) were measured by radioimmunoassay in clinically normal adult ponies (n = 15) and horses (n = 10). The mean serum levels of P-III-P from the ponies, 10.4 +/- 2.9 (SD) ng/mL, and the horses, 12.2 +/- 2.6 (SD) ng/mL, were not significantly different. Segments of jejunum were made ischemic to induce fibrous peritoneal adhesions in two ponies, and serum P-III-P levels were measured on days 4, 5, 7, 14, and 21. An exploratory celiotomy on day 21 revealed that the ischemic injury had induced fibrosis of the mesentery and bowel, but no adhesions h...
Evans PM, Armour MD, Dubielzig RR. To describe the gross and histopathological ocular findings in a horse following suspected lightning injury. Methods: The eyes of a 2-year-old thoroughbred gelding were clinically and histopathologically evaluated following a severe lightning storm following euthanasia because of visual impairment. Results: Severe corneal edema and hydrops were noted clinically oculus dexter. Indirect ophthalmoscopy revealed bilateral symmetrical raised hyporeflective peripapillary geographic lesions. Histopathologic evaluation revealed corneal edema in the right eye with normal corneal endothelium...
Baudler A, Lütkefels E, Drommer W, Deegen E, Ohnesorge B.Epiglottic augmentation by transendoscopic injection of an implant material was performed on ten clinically healthy horses. In six cases bovine collagen (Zyplast) was used, in the remaining four horses the injection was done with polytetrafluorethylene (PTFE-Paste). The results of the surgery were observed endoscopically and by contrast radiography. Using the radiographs, epiglottic length and thickness were measured. For necropsy and histologic assessment the horses, three and two animals of the two groups, were euthanized at three and 12 weeks after surgery. The data obtained from the measur...
Tulleners EP, Becht JL, Richardson DW, Divers TJ.Obstructive choledocholithiasis in a 12-year-old mare was corrected surgically by choledocholithotripsy. The mare had a history of chronic weight loss, intermittent fever, partial anorexia, jaundice, recurrent abdominal pain, and an abdominal mass palpable per rectum. Values for alkaline phosphatase, bilirubin, gamma-glutamyl transferase, sorbitol dehydrogenase, and bromsulpthalein half-life were increased and bilirubinuria was evident before surgery. Two liver biopsies revealed periportal and portal fibrosis, bile duct proliferation, cholestasis, and variable amounts of hepatocellular necrosi...
Magnuson NS, Perryman LE, Suttle DP, Robinson JL, Mason PH, Marta KM.In an attempt to determine the metabolic defect causing severe combined immunodeficiency (SCID) in horses in which altered purine metabolism has been observed, various parameters of purine and pyrimidine metabolism were evaluated. The activities of nine purine enzymes (adenosine kinase, purine nucleoside phosphorylase, deoxyadenosine kinase, deoxycytidine kinase, 5'-nucleotidase, AMP deaminase, hypoxanthine-guanine phosphoribosyl transferase, and adenine phosphoribosyl transferase were measured in fibroblasts. All activities determined for SCID horses were normal. Uptake of 10 microM adenosine...
Bastianello SS, Nesbit JW.The pathological features of biliary atresia in a foal are described. A 4-week-old American Saddler foal was presented for autopsy following an illness characterised by clinical features indicative of hepatic failure. The significant macroscopical lesions occurred in the liver which was extremely enlarged, mottled in appearance and indurated. Bile stasis was evident. Lobular distinction was absent and on sectioning, large bile ducts were absent. A moderate ascites, hydrothorax and hydropericardium and a mild anasarca and intermuscular oedema accompanied the hepatic lesion. The diagnosis of bil...
Schinköthe J, Gerlach K, Ulrich RG, Brehm W.A 12-y-old Shetland Pony was presented with a mucus-secreting fistula in the right paralumbar fossa. Surgery was performed to unravel the origin of the fistula. The horse died under anesthesia and was forwarded to autopsy. The right kidney was markedly atrophic and fibrotic, consistent with unilateral end-stage kidney. The right ureter was markedly thickened, but with luminal continuity leading into the urinary bladder where a partial obstruction caused by nodular para-ureteral fat necrosis was evident. The lumen of the cutaneous fistula was continuous with the right ureter; therefore, we diag...
Lohmann KL, Allen AL.A mature Quarter horse was euthanized following colic of 3 days duration. Postmortem, the large intestine, except the descending colon, was diffusely distended and associated with adhesion of the transverse colon to the pancreas, which had changes consistent with chronic active interstitial pancreatitis. Other lesions included hepatic fibrosis, erosive gastritis, and bilateral adrenal cortical hyperplasia. Pancréatite interstitielle chronique active comme cause d’une obstruction du côlon transversal et de coliques chez un cheval. Un cheval Quarter horse adulte a été euthanasié après de...
Boone LH, Epstein K, Cremer J, Rogers A, Foutz T, Quandt J, Howerth E, Mueller PO.To compare tensile strength, failure location, and histologic features after acute repeat celiotomy through a ventral median (RVM) or a right ventral paramedian (RVP) celiotomy in horses. Methods: Ex vivo experimental study. Methods: Adult horses (N = 18). Methods: Twelve adult horses had original ventral median (OVM) celiotomy. Repeat celiotomy was performed 72 hours postoperatively through the original ventral median (RVM, N = 6) or a RVP (N = 6) celiotomy. Celiotomies were scored daily for edema, drainage, and dehiscence. Fourteen days after repeat celiotomy, horses were eutha...
Leipig M, Abenthum K, Wollanke B, Czupalla I, Esposito I, Steiger K, Hermanns W, Herbach N.A 16-year-old Friesian gelding with relapsing colic was humanely destroyed during diagnostic laparotomy due to suspected abdominal neoplasia. On post-mortem examination, the pancreas appeared as a firm mass (20 × 8 × 8 cm). The cut surface had a lobular structure with multiple cavities. Histological examination revealed severe chronic fibrosing pancreatitis with acinar-ductal metaplasia and duct dysplasia, which was considered to be the cause of the recurrent colic. Formation of tubular complexes within a background of acinar-ductal metaplasia is similar to the regressive lesions detect...
Maekawa Y, Sakamoto T, Umezu K, Ohashi N, Harada Y, Yasukochi S, Takigiku K, Takei K, Nakano Y, Inoue N, Otagiri T, Hashida Y.We report a female infant with acute coronary syndrome after Aubert-Imai modification for transposition of the great arteries. Two months postoperatively, she visited the emergency room because of perspiration and tachypnea. She was diagnosed with acute coronary syndrome by blood chemistry examination. Cardiac catheterization revealed Aubert route stenosis, and emergency operation was performed. The lumen around the aortopulmonary window was almost totally occluded by fibrous tissue extending from the equine pericardial patch. This fibrous tissue was completely resected and the aortopulmonary ...
Macbeth BJ.A 12-year-old Clydesdale gelding was presented for colic and dysuria. Obstructive urolithiasis and chronic renal disease were diagnosed via transurethral endoscopy and percutaneous ultrasonography. Nephroliths, hydronephrosis, and peri-ureteral fibrosis were present. Surgical intervention was declined and the gelding was managed medically with antibiotics and dietary modification. Urolithiase obstructive, hydronéphrose unilatérale et lithiase rénale probable chez un Clydesdale hongre âgé de 12 ans. Un Clydesdale hongre âgé de 12 ans a été présenté pour colique et dysurie. Une urolit...
Evans TJ, Ganjam VK, Miller MA, Niswender KD, Krause WJ, Youngquist RS.Endometrial periglandular fibrosis (EPF) has been proposed as a possible aetiology for equine embryonic and fetal loss. However, the pathophysiology of EPF is not well understood. Angiotensin-converting enzyme (ACE) is found in macrophages, endothelium (during angiogenesis) and myofibroblasts at sites of fibrosis in the heart, kidneys, liver and skin in several species. An increase in local tissue ACE-binding activity appears to be a critical event in the initiation and progression of fibrosis in these tissues. The aim of this study was to investigate the correlation between ACE activity in th...
Machida N, Nakamura T, Kiryu K, Haramaki S, Too K.A 20-year-old pony mare with persistent ventricular tachycardia (VT) was examined cardiopathologically. At necropsy, the heart was enlarged and rounded with both ventricular dilatation. In a longitudinal section of the ventricular septum, a large grayish white patchy lesion (5 x 25 mm) was detected in the relatively higher portion. Microscopically, the lesion was extensive myocardial fibrosis located in the vicinity of the proximal part of the left bundle branch. Partially the fibrotic lesion was in contact with the branch. Such a lesion might play an important role in creating a suitable back...
Sloet van Oldruitenborgh-Oosterbaan MM, van den Ingh TS.A trotter stallion showing symptoms of emaciation was suspected of disease of the liver associated with cholestasis in view of clinical symptoms (poor appetite, sluggishness, jaundice and oedema) and the results of examination of the blood (increased concentrations of gamma-glutamyl, transpeptidase, sorbitol dehydrogenase, alkaline phosphatase, aspartate aminotransferase and markedly increased conjugated bilirubin). A specimen removed at biopsy of the liver revealed the presence of portal fibrosis and severe cholestasis. At autopsy, it was found that very extensive fibrosis of the pancreas (pr...
Imposimato I, Mariella J, Freccero F, Gialletti R.Riboflavin/UV-A corneal cross-linking (CXL) has been applied to treat corneal ulcers in adult horses, but its use in critically ill neonatal foals has not been described. Five cases of hospitalized, critically ill neonatal foals that were in intensive care with corneal ulcers, the ophthalmic treatment, and their outcome up to 1 year are described. A single treatment of CXL phototherapy was performed in three of five foals (five eyes). The application of a riboflavin ophthalmic solution for 20 minutes was followed by the UV-A light irradiation at 30 mW/cm2 for 3 minutes. Topical antibiotic admi...
Jeong S, Franklin SH, Van Eps AW, Lean N, Ahern BJ.Evaluate a prototype dynamic laryngoplasty system (DLPS) in horses; a feasibility study. Methods: 7 healthy Standardbred adult horses. Methods: This was an in vivo experimental study. Horses had a standing surgical procedure to induce complete laryngeal hemiplegia, which was subsequently treated using the dynamic laryngoplasty system (DLPS). Activation of the DLPS was achieved using an injection port exiting through the skin (n = 2) or a subcutaneous injection port (n = 5). For each horse, endoscopic examinations of the upper respiratory tract were performed preoperatively, intraoperatively, a...
Höglund N, Rossi H, Javela HM, Oikari S, Nieminen P, Mustonen AM, Airas N, Kärjä V, Mykkänen A.Equine asthma (EA) is a chronic lower airway inflammation that leads to structural and functional changes. Hyaluronic acid (HA) has crucial functions in the extracellular matrix homeostasis and inflammatory mediator activity. HA concentration in the lungs increases in several human airway diseases. However, its associations with naturally occurring EA and airway remodelling have not been previously studied. Our aim was to investigate the association of equine neutrophilic airway inflammation (NAI) severity, airway remodelling, and HA concentration in horses with naturally occurring EA. We hypo...
Cerveira-Pinto M, Wójtowicz A, Pires MA, Kordowitzki P, Skarzynski D, Ferreira-Dias G, Szóstek-Mioduchowska A, Amaral A.Increased synthesis and deposition of collagen (COL) in the extracellular matrix (ECM) of equine endometrium contributes to endometrosis. Toll-like receptors (TLRs) are transmembrane receptors involved in the innate immune response, recognized for their role in antigen recognition and previously associated with equine endometritis. The TLRs not only recognize pathogen-associated molecular patterns but also regulate inflammations, fibrosis and cancer. The aim of this study was to explore the relationship between TLR expression at different stages of Kenney and Doig's (K-D) grading and COL1 exp...
Martínez-Bartolomé I, Masot J, Serres C.Kenney-Doig scale is considered the international standard method for classifying uterine biopsies in mares; however, its objectivity has been questioned by various studies. In the present study, we analysed the degree of agreement between two pathologists when assessing the same set of 201 uterine biopsies, obtaining a slight to moderate level of agreement (κ = .34/κ = .57). Subsequently, we developed a numerical scale based on the evaluation of histological parameters, including inflammation, fibrosis, glandular density and lymphatic lacunae. Partial scores were summed to obtain a ...
Gómez-Torres F, Ballesteros-Acuña L, Ruíz-Sauri A.Arrhythmic sudden cardiac death in dogs and horses often results from ventricular arrhythmia secondary to myocardial damage. Despite this, limited data exist on the histomorphometric changes in cardiac conduction fibers (CCFs) and cardiac conduction cells (CCCs) following spontaneous myocardial infarction (MI). This study aimed to characterize morphometric and histological alterations in conduction fibers and their junctions with cardiomyocytes in infarcted hearts of horses and dogs. Unassigned: Ten hearts from horses and 10 from dogs that had died suddenly were examined. Histological and immu...
Böck MJ, Fernandez TJ, Pereira VP, da Veiga ML, de Mello Bertoncheli Dos Santos C, de Morais-Pinto L.We examined 52 horse aortas to characterize the morphological aspects of the aortic bulb wall and the ascending aorta. The morphometric data were analyzed using ImageJ®-Fiji 1.5 software. The Tunica intima was composed of endotheliocytes with scarce cytoplasm and ellipsoid nuclei, supported by a collagenous subendothelial stratum. The Tunica media was composed entirely of fascicles of vascular smooth muscle cells interspersed with bundles of collagen fibers and elastic lamellae, characterizing the aortic medial lamellar unit. The Tunica adventitia consisted of two distinct sub-layers: the ext...
Equine chronic degenerative endometritis (CDE) is a progressive process characterized by endometrial fibrosis that could be responsible for alterations of uterine environment and foetal-maternal communication. Objective: The aim of this study was to try to restore this communication by intrauterine administrations of amniotic cell-derived extracellular vesicles (AMC-EVs) in a case series. Methods: Twelve mares were selected on the basis of their reproductive history of early embryonic loss or abortion and clinical suspicion of CDE subsequently verified with histopathological examination of end...
Amaral A, Cerveira-Pinto M, Santos C, Kordowitzki P, Skarzynski D, Ferreira-Dias G, Szóstek-Mioduchowska A.Transforming growth factor (TGF)-β1 is a pro-fibrotic cytokine that affects extracellular matrix (ECM) deposition and fibroblast activity. 17β-Estradiol (E), the dominant ovarian steroid during the follicular phase (FLP) of the estrous cycle, can also influence ECM remodeling and fibrosis, through prostaglandin (PG) synthesis. PGs have opposing roles in fibrosis, with PGE₂ showing anti-fibrotic effects and PGF₂α promoting fibrosis. Equine endometrosis, whose main pathological feature is fibrosis, is marked by chronic inflammation and ECM accumulation, and may involve mediators like TGF-...
